eth0 is a kernel name, and udev renamed it based on PCI geographical location to enp2s1. You forgot to rename the /etc/init.d/net.eth0 symlink to /etc/init.d/net.enp2s1 and perhaps you have put eth0 elsewhere too, like iptables?

eth0 is a kernel name, and udev renamed it based on PCI geographical location to enp2s1. You forgot to rename the /etc/init.d/net.eth0 symlink to /etc/init.d/net.enp2s1 and perhaps you have put eth0 elsewhere too, like iptables?